Projects

As part of North Shore City Council's ongoing programme of sewer separation works, we have been working for the past 12 months to install over 1.2Km of new 1050mm, 900mm and 450mm sewer pipe using predominantly microtunnelling techniques as well as eight large diameter, deep manholes. Features of this project include: Long drives up to 250m between shafts, flat grades of less than less than 0.2%, deep shafts up to 20m deep and challenging ground conditions where unexpected bands of hard sandstone up to 45Mpa were encountered.

Most of the installation has been carried out using our TT1200E drum-cutter machine which was specially adapted to suit the ground conditions including development of a new auger extraction system. The MTS1000A was used for the 450mm installations and we carried out a short hand installation because it suited the line, ground conditions and available resourses.

At time of writing there remains approximately 100LM of the last line to install, half of the structures have been completed and the project is expected to be completed at least 4 weeks ahead of the contract programme. In order to meet or exceed client expectations Harker voluntarily accelerated sections of the working, putting up to three additional crews onto the job to guarantee the completion deadline was met.

Accuracy of installation has been exceptional with all lines installed to well within the contract specified tolerances. This is something we are extremely proud of and is one of the standout features of this particular method of pipeline installation with this machine and a reflection of the high skill level of our TBM operators.

Project Name:

Birkdale A - Sewer

Client:

North Shore City Council

Pipeline Details:

1.4Km of line installed in 1050mm jacking pipe, 900mm open cut and 450mm jacking.

Completed:

June 2009